[clang] [clang-repl] Implement LoadDynamicLibrary for clang-repl wasm use cases (PR #133037)

[Anutosh Bhat via cfe-commits]

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@@ -711,6 +712,14 @@ llvm::Error Interpreter::Undo(unsigned N) {
 }
 
 llvm::Error Interpreter::LoadDynamicLibrary(const char *name) {
+#ifdef __EMSCRIPTEN__
+  void *handle = dlopen(name, RTLD_NOW | RTLD_GLOBAL);
+  if (!handle) {
+    llvm::errs() << dlerror() << '\n';
+    return llvm::make_error<llvm::StringError>("Failed to load dynamic library",
+                                               llvm::inconvertibleErrorCode());
+  }
+#else
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anutosh491 wrote:

Check how we can use the changes here in cppinterop to get dynamic library loaded and symbol addresses fetched at runtime !

https://github.com/compiler-research/CppInterOp/compare/main...anutosh491:CppInterOp:shared_libs

Everything boils down to preload as we know where in the MEMFS our shared lib exists !

https://github.com/llvm/llvm-project/pull/133037